1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2019, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Inline
; use Inline
;
27 with Types
; use Types
;
30 procedure Analyze_Generic_Package_Declaration
(N
: Node_Id
);
31 procedure Analyze_Generic_Subprogram_Declaration
(N
: Node_Id
);
32 procedure Analyze_Package_Instantiation
(N
: Node_Id
);
33 procedure Analyze_Procedure_Instantiation
(N
: Node_Id
);
34 procedure Analyze_Function_Instantiation
(N
: Node_Id
);
35 procedure Analyze_Formal_Object_Declaration
(N
: Node_Id
);
36 procedure Analyze_Formal_Type_Declaration
(N
: Node_Id
);
37 procedure Analyze_Formal_Subprogram_Declaration
(N
: Node_Id
);
38 procedure Analyze_Formal_Package_Declaration
(N
: Node_Id
);
40 procedure Add_Pending_Instantiation
(Inst
: Node_Id
; Act_Decl
: Node_Id
);
41 -- Add an entry in the table of instance bodies that must be analyzed
42 -- when inlining requires its body or the body of a nested instance.
44 function Build_Function_Wrapper
45 (Formal_Subp
: Entity_Id
;
46 Actual_Subp
: Entity_Id
) return Node_Id
;
47 -- In GNATprove mode, create a wrapper function for actuals that are
48 -- functions with any number of formal parameters, in order to propagate
49 -- their contract to the renaming declarations generated for them. This
50 -- is called after the renaming declaration created for the formal in the
51 -- instance has been analyzed, and the actual is known.
53 function Build_Operator_Wrapper
54 (Formal_Subp
: Entity_Id
;
55 Actual_Subp
: Entity_Id
) return Node_Id
;
56 -- In GNATprove mode, create a wrapper function for actuals that are
57 -- operators, in order to propagate their contract to the renaming
58 -- declarations generated for them. The types are (the instances of)
59 -- the types of the formal subprogram.
61 procedure Start_Generic
;
62 -- Must be invoked before starting to process a generic spec or body
64 procedure End_Generic
;
65 -- Must be invoked just at the end of the end of the processing of a
66 -- generic spec or body.
68 procedure Check_Generic_Child_Unit
70 Parent_Installed
: in out Boolean);
71 -- If the name of the generic unit in an instantiation or a renaming is a
72 -- selected component, then the prefix may be an instance and the selector
73 -- may designate a child unit. Retrieve the parent generic and search for
74 -- the child unit that must be declared within. Similarly, if this is the
75 -- name of a generic child unit within an instantiation of its own parent,
76 -- retrieve the parent generic. If the parent is installed as a result of
77 -- this call, then Parent_Installed is set True, otherwise Parent_Installed
78 -- is unchanged by the call.
80 function Copy_Generic_Node
83 Instantiating
: Boolean) return Node_Id
;
84 -- Copy the tree for a generic unit or its body. The unit is copied
85 -- repeatedly: once to produce a copy on which semantic analysis of
86 -- the generic is performed, and once for each instantiation. The tree
87 -- being copied is not semantically analyzed, except that references to
88 -- global entities are marked on terminal nodes. Note that this function
89 -- copies any aspect specifications from the input node N to the returned
90 -- node, as well as the setting of the Has_Aspects flag.
92 function Get_Instance_Of
(A
: Entity_Id
) return Entity_Id
;
93 -- Retrieve actual associated with given generic parameter.
94 -- If A is uninstantiated or not a generic parameter, return A.
96 function Get_Unit_Instantiation_Node
(A
: Entity_Id
) return Node_Id
;
97 -- Given the entity of a unit that is an instantiation, retrieve the
98 -- original instance node. This is used when loading the instantiations
99 -- of the ancestors of a child generic that is being instantiated.
101 procedure Instantiate_Package_Body
102 (Body_Info
: Pending_Body_Info
;
103 Inlined_Body
: Boolean := False;
104 Body_Optional
: Boolean := False);
105 -- Called after semantic analysis, to complete the instantiation of
106 -- package instances. The flag Inlined_Body is set if the body is
107 -- being instantiated on the fly for inlining purposes.
109 -- The flag Body_Optional indicates that the call is for an instance
110 -- that precedes the current instance in the same declarative part.
111 -- This call is needed when instantiating a nested generic whose body
112 -- is to be found in the body of an instance. Normally we instantiate
113 -- package bodies only when they appear in the main unit, or when their
114 -- contents are needed for a nested generic G. If unit U contains several
115 -- instances I1, I2, etc. and I2 contains a nested generic, then when U
116 -- appears in the context of some other unit P that contains an instance
117 -- of G, we compile the body of I2, but not that of I1. However, when we
118 -- compile U as the main unit, we compile both bodies. This will lead to
119 -- link-time errors if the compilation of I1 generates public symbols,
120 -- because those in I2 will receive different names in both cases. This
121 -- forces us to analyze the body of I1 even when U is not the main unit.
122 -- We don't want this additional mechanism to generate an error when the
123 -- body of the generic for I1 is not present, and this is the reason for
124 -- the presence of the flag Body_Optional, which is exchanged between the
125 -- current procedure and Load_Parent_Of_Generic.
127 procedure Instantiate_Subprogram_Body
128 (Body_Info
: Pending_Body_Info
;
129 Body_Optional
: Boolean := False);
130 -- Called after semantic analysis, to complete the instantiation of
131 -- function and procedure instances. The flag Body_Optional has the
132 -- same purpose as described for Instantiate_Package_Body.
134 function Need_Subprogram_Instance_Body
136 Subp
: Entity_Id
) return Boolean;
137 -- If a subprogram instance is inlined, indicate that the body of it
138 -- must be created, to be used in inlined calls by the back-end. The
139 -- subprogram may be inlined because the generic itself carries the
140 -- pragma, or because a pragma appears for the instance in the scope.
143 procedure Save_Global_References
(Templ
: Node_Id
);
144 -- Traverse the original generic unit, and capture all references to
145 -- entities that are defined outside of the generic in the analyzed tree
146 -- for the template. These references are copied into the original tree,
147 -- so that they appear automatically in every instantiation. A critical
148 -- invariant in this approach is that if an id in the generic resolves to
149 -- a local entity, the corresponding id in the instance will resolve to
150 -- the homologous entity in the instance, even though the enclosing context
151 -- for resolution is different, as long as the global references have been
152 -- captured as described here.
154 -- Because instantiations can be nested, the environment of the instance,
155 -- involving the actuals and other data-structures, must be saved and
156 -- restored in stack-like fashion. Front-end inlining also uses these
157 -- structures for the management of private/full views.
159 procedure Save_Global_References_In_Aspects
(N
: Node_Id
);
160 -- Save all global references found within the expressions of all aspects
161 -- that appear on node N.
163 procedure Set_Copied_Sloc_For_Inlined_Body
(N
: Node_Id
; E
: Entity_Id
);
164 -- This procedure is used when a subprogram body is inlined. This process
165 -- shares the same circuitry as the creation of an instantiated copy of
166 -- a generic template. The call to this procedure establishes a new source
167 -- file entry representing the inlined body as an instantiation, marked as
168 -- an inlined body (so that errout can distinguish cases for generating
169 -- error messages, otherwise the treatment is identical). In this call
170 -- N is the subprogram body and E is the defining identifier of the
171 -- subprogram in question. The resulting Sloc adjustment factor is
172 -- saved as part of the internal state of the Sem_Ch12 package for use
173 -- in subsequent calls to copy nodes.
175 procedure Set_Copied_Sloc_For_Inherited_Pragma
178 -- This procedure is used when a class-wide pre- or postcondition is
179 -- inherited. This process shares the same circuitry as the creation of
180 -- an instantiated copy of a generic template. The call to this procedure
181 -- establishes a new source file entry representing the inherited pragma
182 -- as an instantiation, marked as an inherited pragma (so that errout can
183 -- distinguish cases for generating error messages, otherwise the treatment
184 -- is identical). In this call, N is the subprogram declaration from
185 -- which the pragma is inherited and E is the defining identifier of
186 -- the overriding subprogram (when the subprogram is redefined) or the
187 -- defining identifier of the extension type (when the subprogram is
188 -- inherited). The resulting Sloc adjustment factor is saved as part of the
189 -- internal state of the Sem_Ch12 package for use in subsequent calls to
192 procedure Adjust_Inherited_Pragma_Sloc
(N
: Node_Id
);
193 -- This procedure is used when a class-wide pre- or postcondition
194 -- is inherited. It is called on each node of the pragma expression
195 -- to adjust its sloc. These call should be preceded by a call to
196 -- Set_Copied_Sloc_For_Inherited_Pragma that sets the required sloc
197 -- adjustment. This is done directly, instead of using Copy_Generic_Node
198 -- to copy nodes and adjust slocs, as Copy_Generic_Node expects a specific
199 -- structure to be in place, which is not the case for inherited pragmas.
202 (Gen_Unit
: Entity_Id
;
203 Act_Unit
: Entity_Id
);
204 -- Because instantiations can be nested, the compiler maintains a stack
205 -- of environments that holds variables relevant to the current instance:
206 -- most importanty Instantiated_Parent, Exchanged_Views, Hidden_Entities,
207 -- and others (see full list in Instance_Env).
209 procedure Restore_Env
;
210 -- After processing an instantiation, or aborting one because of semantic
211 -- errors, remove the current Instantiation_Env from Instantation_Envs.
213 procedure Initialize
;
214 -- Initializes internal data structures
216 procedure Check_Private_View
(N
: Node_Id
);
217 -- Check whether the type of a generic entity has a different view between
218 -- the point of generic analysis and the point of instantiation. If the
219 -- view has changed, then at the point of instantiation we restore the
220 -- correct view to perform semantic analysis of the instance, and reset
221 -- the current view after instantiation. The processing is driven by the
222 -- current private status of the type of the node, and Has_Private_View,
223 -- a flag that is set at the point of generic compilation. If view and
224 -- flag are inconsistent then the type is updated appropriately.
226 -- This subprogram is used in Check_Generic_Actuals and Copy_Generic_Node,
227 -- and is exported here for the purpose of front-end inlining (see Exp_Ch6.
228 -- Expand_Inlined_Call.Process_Formals).